I wouldn't say they are built to be bought. Israeli entrepreneurs are operating in a system that incentivises selling rather than building a company. Naftali Bennett, the leader of one of the newer parties that just won seats in Knesset election explains this, being an entrepreneur who, himself, sold his company. This, he says, can be remedied if there is the political will, and he makes recommendations how this could be done.
Second, CALL no longer has the constitution of the Israeli start-up. The bulk of operations are in the US albeit with Israeli developers. The facility, in Israel, is secondary.
Third, CALL will eventually be sold, but not before the capitalization is in the multiple of billions. I believe MJ will go international before it is sold.